I have to create a PDF for a potential client and really want to wow them. I am achieving this I hope with the actual content of the document however I want to introduce a limted amount of interactivity.

Specifically I want them to be able to click a food menu and it 'get bigger' for reading. My plan was to have it go to another page where the food menu would be bigger, but my problem is how they get back to where they have come from, and the fact I don't really want the larger food menus to be available as part of the document as pages as such.

Is this at all possible within the confines of PDF? I know how to hyperlink around the document, but I want to give the impression of the client being able to 'zoom' into a food menu and back out again.

You may have to rethink your concept. That's not part of PDF files. Nor any other technology including Adobe Digital Edition for tablets. Unless you've got big bucks to hire an app developer for the iPad.

However, you can have something appear which you click on something else. These are called Show/Hide fields. This works well in PDFs, but may require re-thinking your design.